Technical Field
This invention relates generally to antennas, and more particularly to antennas in wireless communication devices.
Background Art
Wireless communication devices, such as mobile telephones, smart phones, palm-top computers, or personal digital assistants, employ antennas for wireless communication. These antennas are frequently internal antennas embedded within the housing of the wireless communication device. As the devices continue to get smaller, the shrinking physical form factor makes antenna design more difficult. The “electrical length” of the antenna becomes reduced, thereby compromising efficiency. Further complicating matters are the demands to provide additional bandwidth support in one or more antennas disposed within such devices. Moreover, the antennas in these devices are required to function in a variety of conditions, such as with a user's hands placed in different locations, different physical orientations, and so forth. Having one or more fixed antennas with fixed matching circuits can cause the designer to compromise performance of the antenna in some bands to improve the performance in other bands.
It would be advantageous to have an improved antenna configured to operate at increased efficiencies across multiple bands.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.